Hot Tearing Defects of As-Cast Mg-xZn-0.5Y-0.5Zr Alloys

被引：0

作者：

Li X. ^{[1
]}

Liu Z. ^{[1
]}

Wang Y. ^{[1
]}

Wei Z. ^{[1
]}

Wang F. ^{[1
]}

Wang Z. ^{[1
]}

机构：

[1] School of Materials Science and Engineering, Shenyang University of Technology, Shenyang

来源：

Xiyou Jinshu/Chinese Journal of Rare Metals | 2020年 / 44卷 / 07期

关键词：

Hot tearing; I-phase(Mg[!sub]3[!/sub]Zn[!sub]6[!/sub]Y); Mg-xZn-0.5Y alloy; W-phase(Mg[!sub]3[!/sub]Zn[!sub]3[!/sub]Y[!sub]2[!/sub]);

D O I：

10.13373/j.cnki.cjrm.XY19060012

中图分类号：

学科分类号：

摘要：

The effects of different ratios of Zn on hot tearing susceptibility of Mg-xZn-0.5Y-0.5Zr (x=1.5, 2.5, 3.5 and 4.5 (%, mass fraction)) alloys were investigated by self-made "T" mold. The hot tearing tendency was characterized by observing the macroscopic hot crack at the hot spot of the "T" mold and the volume of the crack measured by the paraffin penetrant method. In addition, scanning electron microscope (SEM) was used to analyze the microstructure of the alloy and the free fracture surface of the alloy. The phase analysis was carried out by X-ray diffraction (XRD) and transmission electron microscope (TEM) to determine the main composition of the low melting phase, and then the effect on the thermal cracking defects was studied. The A/D digital-to-analog converter was used to perform temperature-stress acquisition on the solidification. The results showed that the main phases of Mg-xZn-0.5Y-0.5Zr alloy were α-Mg, W-phase (Mg3Zn3Y2) and I-phase (Mg3Zn6Y). With the increase of Zn content from 1.5% to 4.5%, the precipitated phase content at low melting increased obviously, which improved the feeding ability of residual liquid between dendrites, effectively prevented crack initiation and propagation. When the Zn content was low, liquid membrane theory and solidification shrinkage compensation theory were the main theoretical basis for the interpretation of crack initiation. With the increase of Zn content and sufficient feeding of residual liquid, bridging theory was the main mechanisms of hot tearing formation. The order of hot tearing sensitivity of alloys was Mg-1.5Zn-0.5Y-0.5Zr, Mg-2.5Zn-0.5Y-0.5Zr, Mg-3.5Zn-0.5Y-0.5Zr, Mg-4.5Zn -0.5Y-0.5Zr. © Editorial Office of Chinese Journal of Rare Metals. All right reserved.

引用

页码：697 / 705

页数：8

共 41 条

[11]

Li M, Wang H W, Zhu Z J, Wei Z J., Effects of scraps and yttrium on the as-casting microstructure, hot tearing and solidification characteristics of ZL205A alloy, Rare Metal Materials and Engineering, 39, s1, (2010)

[12]

Wei Z Q, Wang Y, Liu Z., Effects of Zn and Y on hot-tearing susceptibility of Mg-xZn-2xY alloys, Mater. Sci. Technol, 34, 16, (2018)

[13]

Liu Z, Zhang S B, Mao P L, Wang F., Effects of Y on hot tearing susceptibility of Mg-Zn-Y-Zr alloys, Trans. Nonferrous. Met. Soc, 24, 4, (2014)

[14]

Wang Z, Li YZ, Wang F., Hot tearing susceptibility of Mg-xZn-2Y alloys, Transactions of Nonferrous Metals Society of China, 26, 12, (2016)

[15]

Wang Z, Huang Y D., Experiment and numerical analysis of hot tearing susceptibility for Mg-Y alloys, J. Mater. Sci, 49, (2014)

[16]

Wang W L, Lei N N, Qiu Y L, Jia J D, Yan X., Effect of Ce on microstructure and mechanical properties of Mg-Y-Zr rare earth magnesium alloy, Chinese Journal of Rare Metals, 42, 4, (2018)

[17]

Huang Z H, Zhang Y, Chen R S, Han E H., Hot tearing susceptibility of Mg-Zn-Y-Zr alloys, Foundry, 58, 8, (2009)

[18]

Dahle A K, Lee Y C, Nave M D., Development of the as-cast microstructure in magnesium-aluminium alloys, Journal of Light Metals, 1, 1, (2001)

[19]

Wen L, Ji Z, Li X., Effect of extrusion ratio on microstructure and mechanical properties of Mg-Nd-Zn-Zr alloys prepared by a solid recycling process, Mater. Charact, 59, 11, (2008)

[20]

Qiang L, Wang Q, Wang Y., Effect of Nd and Y addition on microstructure and mechanical properties of as-cast Mg-Zn-Zr alloy, J. Alloys Compd, 588, 1-2, (2013)

← 1 2 3 4 5 →